Covariance , Dynamics and Symmetries , and Hadron Form Factors
نویسندگان
چکیده
We summarise applications of Dyson-Schwinger equations to the theory and phenomenology of hadrons. Some exact results for pseudoscalar mesons are highlighted with details relating to the U A (1) problem. We describe inferences from the gap equation relating to the radius of convergence for expansions of observables in the current-quark mass. We recapitulate upon studies of nucleon electromagnetic form factors, providing a comparison of the ln-weighted ratios of Pauli and Dirac form factors for the neutron and proton.
منابع مشابه
Deformed Symmetry in Snyder Space and Relativistic Particle Dynamics
We describe the deformed Poincare-conformal symmetries implying the covariance of the noncommutative space obeying Snyder’s algebra. Relativistic particle models invariant under these deformed symmetries are presented. A gauge (reparametrisation) independent derivation of Snyder’s algebra from such models is given. The algebraic transformations relating the deformed symmetries with the usual (u...
متن کاملHeavy Hadron Spectrum and Interactions
Starting from the approximate symmetries of QCD, namely chiral symmetry for light quarks and spin and flavor symmetry for heavy quarks, we investigate the low-energy properties of heavy hadrons. For this purpose we construct a consistent picture of quark-antiquark and quark-diquark interactions as a low-energy approximation to the flavor dynamics in heavy mesons and heavy baryons, respectively....
متن کاملHadron Therapy in Iran: Patient Indication Estimation and Challenges Ahead
Introduction: Radiotherapy with heavy charged particles such as protons and carbon ions (hadron therapy) has been recognized as an advanced technique for the treatment of various cancers. For some indications such as pediatric and radio-resistant tumors, it is considered the preferred method. However, despite its remarkable benefits, development of hadron therapy centers in the...
متن کاملLorentz covariance of three - dimensional equations
We show how the invariance under the charge conjugation and CPT symmetry, present in the Bethe-Salpeter equation, is lost in the reduction to certain relativistic three-dimensional equations. This in particular leads to the breakdown of the standard Lorentz structure and renormalization procedures for the resulting single-particle propagators. We formulate the equal-time approximation of the Be...
متن کاملTwisted Symmetry in Snyder Space and Relativistic Particle Dynamics
We describe the twisted Poincare-conformal symmetries implying the covariance of the noncommutative space obeying Snyder’s algebra. Relativistic particle models invariant under these twisted symmetries are presented. A gauge (reparametrisation) independent derivation of Snyder’s algebra from such models is given. The algebraic transformations relating the twisted symmetries with the usual (untw...
متن کامل